Q63.If the sum of an infinite GP, a, ar, ar2, ar3, … is 15 and the sum of the squares of its each term is 150, then the sum of ar2, ar4, ar6, … is: (1) 25 (2) 9 2 2 (3) 1 (4) 5 2 2
What This Question Tests
The question requires solving a system of two equations involving the sum of an infinite GP and the sum of the squares of its terms, then finding the sum of another related GP.
Concepts Tested
Formulas Used
S = a/(1-r)
S_sq = a^2/(1-r^2)
📚 NCERT Sections This Tests
2.2 — A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 · Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
2.5 — A Parallel Plate Capacitor With Air Between The Plates Has A
Physics Class 11 · Chapter 2
2.5 A parallel plate capacitor with air between the plates has a capacitance of 8 pF (1pF = 10–12 F). What will be the capacitance if the distance between the plates is reduced by half, and the space between them is filled with a substance of dielectric constant 6?
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Geometric Progression
- Year
- 2021
- Shift
- 26 Aug Shift 1
- Q Number
- Q63
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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